This study is to determine if preterm infants fed reformulated Similac Special Care Formula in hospital and a 22 kcal/fl oz specially designed discharge formula after reaching a weight of 1800 grams have a greater bone mineral content and improved growth, compared to preterm infants fed Similac Special Care Formula in hospital and Similac with Iron after 1800 grams. This study will include 44 healthy, preterm infants assigned one of two feeding regimens using a blinded, randomized design.